The invention concerns the field of antifriction materials produced using a method of powder metallurgy, and can be applied to the machine-building industry to produce units of sliding friction for various machines, mechanisms and equipment.
The properties of existing antifriction materials have proved to be insufficient to ensure a satisfactory service life between maintenance and repairs of machines, mechanisms and equipment.
A patent on rolling of metal powder was issued in 1902, however, only after 35-40 years did it start to be practically applied. During World War II, by means of rolling of iron powder, guiding slides for artillery shells were produced in Germany. Herhard Nezer reported this in the fourth International Congress of Engineers and Mechanics in 1952 in Stockholm [1]. After that report, development of a method of rolling of powder began in USA and it was first applied in nuclear engineering. H.Hauzner and S. Stockheim Sylvania Co. (USA) initiated production of metal-cermets rolling from powder of thorium, uranium and plutonium, powder of tungsten and mixture of tungsten with a dioxide of uranium. Then, roll stock out of steel powder was manufactured by other corporations that worked in the field of nuclear fuel, such as Whitecker Metals Corporation, Glen Martin Company and others [1].
In the following years in the USA, after introduction of special rolling mills, industrial application of rolling of powder expanded. Production of tape and leaves out of black and color materials powder began in the USA by Hiden Metals Company, which in 1959 introduced semi-industrial mechanisms for rolling copper and other metals powder [1].
Bliss (Ohice) Company mastered production of a commodity copper tape, which was cheaper comparing to alloyed tape.
In 1959, the Republic Steel Co. disclosed the completion of development of technological process of continuous rolling of iron powder. In England, Mond Nickel company rolled out of nickel-ferrous powder honeycombless leaves 0.25 mm thick and up to 300 mm long. Industrial production of leaves out of titanium powder was also initiated [1].
The technology of producing various types of powder rolling products including liners of blocks of bimetallic and multi-layer roll stock, has been developed more recently.
Antifriction two-layer materials on steel substrate with babbitt by a working stratum (babbit is soldered onto the steel substrate, the substrate being one of the layers) are known [2]. These materials have found wide application in modern engines and in bearings of liquid friction.
Deficiencies of these materials are a low fatigue resistance of 1,13 kg/mm, origin of scores (mechanical damages) at the moment of starting and hitch at termination of feeding of liquid lubricant, as the babbitt works only at plentiful liquid lubricant and low speeds of slide.
Also known are materials in which a layer of mixture of powder, for example a layer of babbitt of about 75 microns thick, is baked on a steel substrate [2]. This triple material (the mixture of copper and nickel powders is soldered onto the steel substrate, then it is saturated with babbitt, the substrate being one of these layers) has found broad application since 1940 in the USA for crankshafts and crankshaft rod bushings of automobile and air engines and diesel engines. It works with loadings 15-20% higher than the best babbitt containing tin and lead. Design load for this material is 140 kg/cm.sup.2.
Deficiencies of this material are its high cost, low fatigue resistance, low unit loads, operation only at plentiful liquid lubricant, origin of scores at termination of feeding of liquid lubricant, impossibility to produce blocks weighing over 15 kg.
Another material is known [2] which comprises a steel substrate and a layer of lead-containing bronze, with the following relation of components, in mass %:
Lead 10-40 Tin 0-10 Copper rest
Deficiencies of this material are its high cost, the fact that it contains lead, which increases harmful substances in air and is a ground of pollution during manufacture and maintenance, and its low mechanical strength, as lead reduces temperature of baking to 820.degree. C. because it evaporates intensively at a higher temperature, so that it sharply reduces the hardness of bronze and, consequently, its endurance. Since copper and lead are almost non-soluble in each other, the material has a two-phase structure consisting of grains of lead and copper; therefore the bronze stratum of a bimetal has a low mechanical strength. Moreover, the working surface lead-containing bronze does not immerse deposited solid particles, so that it requires a high scale of purifying lubricant oil or lamination on the working surface of an alloy lead and tin or lead and indium, which sharply increases the cost of material, and pollutes the environment.
Other materials are known which comprise a steel substrate and a porous stratum baked and permeated with fluorocarbon filling [2]. These materials have high mechanical strength, thermal conduction and bearing capacity. Materials of this type, operating with a lack of lubricant, are permeated with fluorocarbon filling (lead and disulphide of a molybdenum) or, for operation with minimum lubricant, are permeated with acetate-copolymer.
Deficiencies of these materials are the high friction coefficient of 0.13, and consequently, insufficient resistance, high complexity and cost, impossibility to manufacture blocks weighing over 15 kg.
Other materials are known which comprise a steel substrate and a layer of powder of granules of spherical tin bronze containing 0-10 units of bronze, with subsequent sealing [2].
Deficiencies of these materials are low mechanical and hydrodynamic hardness, as the tin reduces temperature of baking to 780.degree. C. since it evaporates intensively at higher temperatures, and consequently, the hardness of bronze and its endurance are sharply reduced. The tin bronze cannot be utilized for operation in heavy-loaded clusters. The manufacture of blocks weighing over 15 kg is impossible.
Other materials are known which comprise a steel substrate and a layer of powder of bronze graphite containing 8-4 (stannic-graphite bronze with the mass % content of bronze and graphite: bronze-8 mass %, graphite-4 mass %), 9-3 and 10-3 of bronze [3]. The content of graphite in these materials makes 3-4% of total mass.
Deficiencies of these materials are the low graphite content below 4,5%; at such content, it cannot create a separating skin on the surface of the material, which causes higher wear of the contacting pairs.
Further, antifriction materials are known which contain zinc. For example, the proportions of the components of such a material [4] are as follows, in mass %:
 Zinc 8.0 Iron 4.5 Lead 3.0 Graphite 6.0 Quartz 4.0 Disulphide of molybdenum 6.0 Copper Rest
Deficiencies of this material are its low hardness, as lead reduces temperature of baking to 820.degree. C., the content of free graphite over 5% which sharply weakens the material, the presence of lead which increases the content of harmful substances in air and a ground during manufacture and maintenance.
At temperature over 550.degree. C., zinc evaporates sharply, which weakens the material. As a result this material does not have sufficient hardness and endurance.
Other antifriction materials are known [5], in which the composition is the following, in mass %:
 Carbon 1-5 Copper sulfides 1-10 Alloy Fe--Cr 0.2-5.0 Copper Rest
Deficiencies of these materials are poor lubricating properties, high friction coefficient, heightened wear of coupled surfaces in connection with the content in its composition of carbides of chrome and impossibility of manufacturing work pieces weighing over 5 kg.
Another antifriction material is known [6] which comprises a copper basis and has the following composition, in mass %:
 Iron 3-6 Graphite 2-5 Tin 9-12 Copper Rest
Deficiencies of this material are the heightened wear of pairs of abrasion due to an insignificant content of graphite, which, consequently, does not prevent connection between the materials of contacting pair, low mechanical strength, as the tin does not allow to increase temperature of baking over 820.degree. C., which is completely insufficient for manufacturing workpieces weighing over 5 kgs, and high cost due to the presence of expensive and scarce tin.
Another antifriction material on a copper basis is known [7]which contains the following components, in mass %:
 Graphite 15-16 Tin 9-10 Lead 10-12 Copper Rest
Deficiencies of this material are its low mechanical strength due to content of free graphite in the amount over 10% of total mass, which sharply weakens the material, and consequently its low resistance, impossibility of application with high load in heavy operational requirements, presence of lead, which increases the density of harmful substances in air and ground during manufacture and maintenance, and high cost due to content of expensive tin and lead.
Another antifriction material on copper basis is known [8], which contains the following components, in mass %:
 Iron 9-18 Fluorides of calcium, selenium, barium 10-40 Copper Rest
Deficiencies of this material are high wear of pairs of abrasion due to lack of graphite, which, consequently, does not prevent connection between materials of contacting pairs and impossibility of contacting pairs weighing over 5 kg.
Finally, another antifriction material is known [9], which contains powder of copper, iron, phosphorus, graphite and zinc at the following proportions, in mass %:
 Phosphorus 0.48-1.20 Iron 9.6-12.0 Zinc 2.4-16.0 Graphite 10.5-25.0 Copper Rest
In this material, 10-21% of graphite and 9,0-15,0% of copper make up the material as granules having a diameter in the range of 0.4-2.0 mm.
An important deficiency of this material is its low mechanical strength, as zinc does not allow to increase temperature of baking over 820.degree. C. due to intensive evaporation of zinc, whereas, for deriving a material on a copper basis with high mechanical characteristics containing 9.6-12.0% of iron, temperature of baking should not be below 1000.degree. C.